you can also go with starter strips and let them build their own. in that case, i would buy one bunch of foundation so that you can put one full frame in as a guide and either use wax or wood, etc. as a start for all others.
you can research foundationless on here. in my opinion, letting the bees build the cells that they need is the best choice. it has some potential drawbacks, but if you do your homework, those relatively minor issues can be avoided or easily overcome. + it saves money ;-)